Journal of Applied Physiology, Vol 43, Issue 2 365-369, Copyright © 1977 by American Physiological Society
Hematologic responses to carbon monoxide and altitude: a comparative study
M. F. Thomas and D. G. Penney
Groups of 40- and 90-day-old rats were exposed to 500 ppm CO (HbCO=31-43%)
and simulated altitude (15,000 ft). Resulting hematologic changes were
monitored after 1 day, 1 wk, 3-4 wk, and 9-11 wk of exposure. The two
treatments resulted in similar changes in hemoglobin (Hb) and hematocrit
ratio (Hct) in the young rats, while in the older group there were several
small, but significant differences in these parameters. Mean corpuscular
hemoglobin concentration (MCHC) fell 12.4-15.1% during the 1st wk of
exposure in all groups except the young altitude rats, which remained at
the control value. The former groups returned to control levels by the 3rd
to 4th wk of exposure. Red cell 2,3-diphosphoglycerate (2,3-DPG) increased
21.6-26.1% above control during 3-4 wk of altitude exposure, but later
(9-11 wk) returned toward control levels. CO exposure resulted in a sharp
decrease in 2,3-DPG after 1 day of exposure only in the young rats. 2,3-DPG
level progressively decreased with age in control rats. The effects of CO
and altitude although similar in several respects (i.e., Hb, Hct, MCHC)
differ with regard to red cell 2,3-DPG.
